Fiber glassing question

I think I would use stainless T nuts on the bottom of the board instead of having those bolts sticking up. would consider gluing the board down with 5200? before glassing it in.
bumpy

OK this is driving me a little nuts! The whole issue is {what will bond aluminum to fiberglass}! The 3m website does not say 5200 will bond aluminum except (maybe) and not as well as wood or other materials, and only if I prime the "metal". It does not say what kind of metal or what to prime it with. Also I can not find out if epoxy
and or what kind of epoxy will be strong enough to create a good bond that is why I was looking at fiber glassing a base and using mechanical "bolts" and also 5200 on top of it all for some give due to vibration ext. then bolting it down. I just want the grab rail to become part of the boat and not come off. I am thinking I will first try something and bear with me. Drilling several holes in the base plate so the 5200 can ooze through. Then using like 8 screws to the deck for a mechanical bond. I am about to just get some 8' bolts and go through the whole dang hull! LOL

To answer your questions directly, alodine or anodize can be used as a primer for Al. But you don't have to turn this into a science project. Very simply there are 2 types of bonds chemical bonds and mechanical bonds. Primers are need for chemical bonds, abrading the surface is what you need for mechanical bonds. Something like 80 grit sand paper is all you need to abrade the surface of the Al and the epoxy with bond to it. If you glass the Al base in as I described in a previous post the load applied to the handle will be reacted through the glass that has encapsulated the Al base and the bond line becomes secondary. Any marine store like West Marine will carry a good epoxy for what you want to do. When you glass in the base extend the plies over the base 4 ins or so and if you use 4-5 plies taper the edge by 1/2 in for each ply. This will minimize the peel loads at the edge of the glass overlay. Even if something does not go as planned you can always add 4 through bolts one in each corner and seal with the 5200, and you will have a nice solid base. Hope this helps. Good luck with your project.